Ask Raf: The Salt Shakedown
A column on food science, history, and culture
Please settle a dispute between my husband and me: I add salt while cooking. He adds it at the end. Which is correct? Also, we want to know: What’s the difference between kosher, table, and sea salt?
Like all great disputes, yours gets to the very heart of the matter while leaving no clear winner. At base is the unique nature of salt, which is one of the most ubiquitous and unusual ingredients we cook with. Salt—made up primarily of sodium chloride—plays two main roles in the kitchen.
When your husband adds salt at the end of cooking, he is enhancing and modifying the food’s flavors and aromas. Salt suppresses our perception of bitterness, accentuates sweetness, and makes our food more aromatic.
This last feat is accomplished by chemically altering the food, causing aroma molecules to enter the air where we can better perceive them. Also, by salting at the end of cooking, he increases the sensation of saltiness and takes advantage of the shape of the salt crystals before they dissolve: bigger ones lend a pleasant crunch and a lingering saltiness, smaller ones a quick, salty burst.
Your technique of salting while cooking illustrates the way salt acts not only as a flavor modifier, but also as a powerful chemical tool to change the way ingredients behave when cooked. Salt, for example, helps prevent the proteins in eggs from squeezing out moisture and making your scramble tough and dry. It also helps break down the cellular structure of vegetables— salting as they steam or boil makes them soften more quickly. Additionally, salting during cooking makes for more consistent saltiness throughout the dish.
The earliest known saltworks — places where salt is harvested or produced— date to around 6000 B.C. in China, where it was harvested from a salty lake. While salt manufacturing has come a long way in the subsequent millennia, it’s taken us to a place of relative uniformity.
Table salt is a recent invention, dating to 1887, when the vacuum pan salt evaporator was invented. This technique requires salty brine, which is created by pumping water into, and then out of, underground rock salt deposits. The resulting brine is boiled down through a series of heated, vacuum- sealed chambers until uniform crystals are produced. Because other minerals naturally found in the rock salt deposits build up and clog the piping, they are removed from the brine, leaving almost pure sodium chloride.
Kosher salt is made from the same purified brine, but shaped into larger, more porous crystals. While koshering meat is a historic practice, most likely originally accomplished with large- grained rock salt to draw blood and impurities out of raw meat, kosher salt as we know it is a 20th-century invention of American salt companies targeting the Jewish market.
While sea salt has its origins in seawater, almost all commercial sea salt has been evaporated on an industrial scale and highly refined to remove “impurities,” making it almost chemically identical to table and kosher salt.
Fear not: Many producers all over the world are making high-quality, unrefined sea salt on a smaller scale that takes advantage of the specific mineral content of its source for full, complex flavors — merroir to wine’s terroir. Here in Oregon, the Jacobsen Salt Company makes salt from Netarts Bay water, which is known for its bright, clean flavor. When you have this beautifully flavorful salt in hand, use your husband’s tactic: Salt at the end.
Raf Spielman plays drums in a rock band as an excuse to tour the country sampling delicious regional cuisines.
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